Title of Invention

A PROCESS FOR THE PREPARATION OF AN EMULSIFIABLE MYCO-CHEMICAL HERBICIDE CONCENTRATE

Abstract

A process for the preparation of an emulsifiable myco-chemical herbicide concentrate comprising mixing under stirring at 26&#730;C±2&#730;C 10<7> to 10¹&#8308; spores/g or ml of alternaria alternata, 10 to 15 % by weight of a phenyl-thio-pyrimidine of the formula I wherein X is a halogen atom such as flouro, chloro, bromo or iodo and M is an alkali metal ion such as sodium or potassium, 15 to 50% by weight of surfactant(s) and 50 to 75% by weight of water.

Full Text

FORM 2 THE PATENTS ACT, 1970 As amended by the Patents (Amendment) Act, 2002 COMPLETE SPECIFICATION (See Section 10; Rule 13) TITLE A process for the preparation of an emulsifiable myco-chemical herbicide concentrate APPLICANTS Godrej Agrovet Limited, Pirojshanagar, Eastern Express Highway, Vikhroli (East), Mumbai 400 079, Maharashtra!, India, an Indian Company INVENTORS Under Section 28(2) Bohra Burhanuddin, Dr Vyas Brahmanand Ambashankar, Dr Mistry Keki Bamanshaw and Godrej Nadir Burj or, all of Godrej Agrovet Limited, Pirojshanagar,Eastern Express Highway, Vikhroli (East), Mumbai 400 079, Maharashtra India, all Indian Nationals The following specification particularly describes the nature of this invention and the manner in which it is to be performed FIELD OF INVENTION This invention relates to emulsifiable myco-chemical herbicide concentrate and process for the preparation thereof. PRIOR ART Cotton crops like several other cultivated crop plants get infested by a variety of weeds. The most predominant and obnoxious of them is Trianthema portulacastrum. Herbicidal compositions of phenyl-thio- pyrimidinesofthe Formula I Formula I wherein X is a halogen atom such as flouro, chloro, bromo or iodo and M is an alkalimetal ion such as sodium or potassium, are reported to possess excellent herbicidal activity against perennial and annual weeds and have at the same time a high level of safety to the crop plants. The surfactants and dispersing agents used in the preparation of the above compositions are alcohol sulfuric acid ester, alkyl aryl sulfonate, lignin sulfonate, polyoxy ethylene glycol ether, polyoxyethylene alkyl aryl ether or polyoxyethylene sorbitol monoalkylate (US Patent No 4932999). Phytopathogenic fungi, Alternaria alternata is reported to cause disease in the Trianthema portulacastrum weeds eventually leading to their death (Bohra et al. 2004, Publication communicated to Indian Phytopathology). OBJECTS OF INVENTION An object of the invention is to provide an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops which is very effective in controlling Trianthema portulacastrum weeds. Another object of the invention is to provide an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops which has low persistence in theenvironment and is environment friendly. Another object of the invention is to provide an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops,, which- is economical. Another object of the invention is to provide an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops which is storage stable. Another object of the invention is to provide a process for the preparation of an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops which is very effective in controlling Trianthema portulacastrum weeds. Another object of the invention is to provide a process for the preparation of an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops which has low persistence in the environment and is environment friendly. Another object of the invention is to provide a process for the preparation of an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops which is economical. I Another object of the invention is to provide a process for the preparation of an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops which is storage stable. Another object of the invention is to provide a process for the preparation of an emulsifiable myco-chemical herbicide concentrate for crops, especially cotton crops which is simple, easy and convenient to carry out. Another object of the invention is to provide a method of effectively controlling Trianthema portulacastrum weeds in crops, especially cotton crops using the emulsifiable myco- chemical herbicide concentrate. DESCRIPTION OF THE INVENTION According to the invention there is provided an emsulsifiable myco-chemical herbicide concentrate comprising 107 to 1014 spores/g or ml of Altemaria alternata, 10 to 50 % by weight of a phenyl-thio-pyrimidine of the Formula I Formula I wherein X is a halogen atom such as flouro, chloro, bromo or iodo and M is an alkalimetal ion such as sodium or potassium, 15 to 50 % by weight of surfactant(s) and 50 to 75 % by weight of water. The surfactants / dispersing agents used in the invention may be any known surfactant / dispersing agent including those reported in US Patent No 4932999. Ethoxylated lauryl alcohol and ethoxylated octyl phenol are preferred surfactants as they have low persistence in the environment and are environment friendly. Also they occur in nature and are easily available and cheap. Preferably, the emulsifiable myco-chemical herbicide concentrate comprises 10 to 10 spores/g or ml of Alternaria alternata, 10 to 15 % by weight of a phenyl-thio-pyrimidine of the Formula I, 15 to 50 % by weight of the surfactants ethoxylated lauryl alcohol and ethoxylated octyl Still preferably, the emulsifiable myco-chemical herbicide concentrate comprises 25 % by weight of the surfactants ethoxylated lauryl alcohol and ethoxylated octyl phenol in the weight ratio of 25 : 75 to 75 : 25. Preferably, the emulsifiable myco- chemical herbicide concentrate comprises sodium 2-chloro-6-[4,6-dimethoxy-2-pyrimidinyl)thio] benzoate. According to the invention there is also provided a process for the preparation of an emsulsifiable myco-chemical herbicide concentrate comprising mixing under stirring at 26°C ± 2°C 107 to 1014 spores/g or ml of Alternaria alternate, 10 to 50 % by weight of a phenyl-thio-pyrimidine of the Formula I wherein X is a halogen atom such as flouro, chloro, bromo or iodo and M is an alkalimetal ion such as sodium or potassium, 15 to 50 % by weight of surfactant(s) and 50 to 75 % by weight of water. Preferably, the process comprises mixing 107 to 1011 spores/g or ml of Altemaria alternata, 10 to 15 % by weight of a phenyl-thio-pyrimidine of the Formula I, 15 to 50 % by weight of the surfactants ethoxylated lauryl alcohol and ethoxylated octyl phenol in the weight ratio of 10 : 90 - 90 : 10 and 50 to 75 % by weight of water. Still preferably, the process comprises mixing 25 % by weight of the surfactants ethoxylated lauryl alcohol and ethoxylated octyl phenol in the weight ratio 25 : 75 to 75 : 25. Preferably the process comprises mixing sodium 2-chloro-6-[4,6-dimethoxy-2-pyrimidinyl)thio] benzoate. According to the invention there is also provided a method of effectively controlling Trianthema portulacastrum weeds in crops especially cotton crops by applying or spraying the emulsifiable myco-chemical herbicide concentrate described above. The herbicide concentrate of the invention is diluted with water in the volume ratio 1 : 400 to 1 : 1600 prior to applying or spraying on the Trianthema portulacastrum weeds. The following experimental examples are illustrative of the invention but are not limitative of the scope thereof: Example 1 Five hundred ml spore suspension of Alternaria altemata (1011 spores / ml) was mixed with 31.25g sodium 2-chloro-6-[4,6-dimethoxy-2-pyrimidinyl)thio] benzoate, 78.12g ethoxylated lauryl alcohol and ethoxylated octyl phenol (25% w/w) in the weight ratio 25 : 75 and 500 litres of water under stirring at 26+2°C to obtain a spray solution for one hectare area containing 108 spores/ ml of fungus Alternaria altemata, 0.00625% by weight of the sodium 2-chloro-6-[4,6-dimethoxy-2-pyrimidinyl)thio]benzoate and 0.0156 % by weight of ethoxylated lauryl alcohol and ethoxylated octyl phenol. Example 2 Five hundred ml spore suspension of Alternaria alternata (1010 spores / ml) was mixed with 46.875g sodium 2-chloro-6-[4,6-dimethoxy-2-pyrimidinyl)thio] benzoate, 117.18g ethoxylated lauryl alcohol and ethoxylated octyl phenol ( 25% w/w) in the weight ratio 75 : 25 and 500 litres of water under stirring at 26+2°C to obtain a spray solution for one hectare containing 107 spores/ ml of fungus Alternaria alternata, 0.0093% by weight of the sodium 2-chloro-6-[4,6-dimethoxy-2-pyrimidinyl )thio]benzoate and 0.0156 % by weight of ethoxylated lauryl alcohol and ethoxylated octyl phenol. Using the myco-chemical herbicide concentrates of Examples 1 and 2 comparative studies were carried out on 28 days old Trianthema portulacastrum weeds by spraying only once on one hectare of cotton crops divided into 8 equal zones. The results recorded after 20 days of spraying were as given in the following Table: TABLE SN Treatments in 500 litres of spray solution / ha Percentage of Mortality of Trianthema Plants Percentage of loss in bio mass over control 1 Spray of aqueous suspension of Alternaria alternata (108 spores/ml.) in zone 1 63.3 87.7 2 Spray of aqueous suspension of Altemaria alternata (108 spores/ ml) followed by Pyrithiobac sodium (31.25 g/ha) after 4 days in zone 2 58.3 87.5 3 Spray of Pyrithiobac sodium (31.25 g/ha) followed by aqueous suspension of Altemaria alternata (10 spores/ml) after 4 days in zone 3 17.8 86.2 4 Spray of pyrithiobac sodium (31.25 g/ha) in zone 4 20.7 77.2 5 Spray of pyrithiobac sodium (62.5 g/ha) in zone 5 92.0 89.3 6 Herbicide concentrate of Example 1 in zone 6 89.5 89.0 7 Herbicide concentrate of Example 2 injzone 7 88.7 88.9 8 -Control (water spray) 0.0 0.0 Pyrithiobac sodium is a commonly used cotton herbicide comprising sodium 2-chloro-6-[4-6-dimethoxy-2-pyrimidinyl} thio]benzoate. The data in the above Table clearly show that the herbicide concentrates of Examples 1 and 2 were very effective and their efficacy was comparable to that of Pyrithiobac sodium applied at the recommended dose of 62.5 g/ha (SN 6 and 7 and SN 5). When Alternaria altemata and Pyrithiobac sodium were alternated with the dosage of Pyrithiobac sodium reduced by half (31.25g/ha), the efficacy was considerably low (SN 2 and 3). Further the efficacy of Altemaria altemata and that of Pyrithiobac sodium at half the dosage when sprayed individually was also reduced considerably (SN 1 and 4). The herbicide concentrate of the invention is economical in that it comprises Alternaria alternata which is naturally occurring and is inexpensive and in that at the application stage it requires reduced quantity of the expensive phenyl-thio pyrimidines and surfactants per hectare. Due to the reduced quantity of the surfactants, persistence of the surfactants in the environment is reduced thereby reducing environmental problems. The surfactants ethoxylated lauryl alchol and ethoxylated octyl phenol have low persistence in the environment as compared to the other surfactants and dispersing agents reported . Therefore, herbicide concentrate of the invention comprising ethoxylated lauryl alcohol and ethoxylated octyl phenyl has still low persistence in the environment and is further environment friendly. Ethoxylated lauryl alcohol and ethoxylated octyl phenol are also naturally occurring and easily available and cheap. Using the above surfactants in the herbicide concentrate of the invention, it can be made further economical. The process of the invention involves simple mixing of the ingredients and is therefore, simple, easy and convenient to carry out. The herbicide concentrates of Examples 1 and 2 was stored for 6 months and was found to be quite stable at the end of 6 months. WE CLAIM 1. A process for the preparation of an emulsifiable myco-chemical herbicide concentrate comprising mixing under stirring at 26°C ± 2°C 107 to 1014 spores/g or ml of Alternaria alternata, 10 to 50 % by weight of a phenyl-thio-pyrimidine of the Formula I wherein X is a halogen atom such as flouro, chloro, bromo or iodo and M is an alkali metal ion such as sodium or potassium, 15 to 50 % by weight of surfactant(s) and 50 to 75 % by weight of water. 2. A process as claimed in claim 1 which comprises mixing 10 to 10 spores/g or ml of Alternaria alternata, 10 to 15 % by weight of a phenyl- thio-pyrimidine of the Formula I, 15 to 50 % by weight of the surfactants ethoxylated lauryl alcohol and ethoxylated octyl phenol in the weight ratio of 10 : 90 - 90 : 10 and 50 to 75 % by weight of water. S. A process as claimed in claim 1 or 2, which comprises mixing 25 % by weight of the surfactants ethoxylated lauryl alcohol and ethoxylated octyl phenol in the weight ratio 25 : 75 to 75 : 25. 4. A process as claimed in any one of claims 1 to 3 which comprises mixing sodium 2-chloro-6-[456-dimethoxy-2-pyrimidinyl)thio] benzoate. 5. A process for the preparation of an emulsifiable myco-chemical herbicide concentrate substantially as herein described particularly with reference to Examples 1 and 2. Dated this 18th day of May 2004 (Jose M A) of Khaitan & Co Agent for the Applicants

Documents:

579-mum-2004-cancelled pages(06-09-2004).pdf

579-mum-2004-claims(granted)-(06-09-2004).doc

579-mum-2004-claims(granted)-(06-09-2004).pdf

579-mum-2004-correspondence(18-05-2004).pdf

579-mum-2004-correspondence(ipo)-(20-07-2004).pdf

579-mum-2004-form 1(07-06-2004).pdf

579-mum-2004-form 1(20-05-2004).pdf

579-mum-2004-form 19(07-06-2004).pdf

579-mum-2004-form 2(granted)-(06-09-2004).doc

579-mum-2004-form 2(granted)-(06-09-2004).pdf

579-mum-2004-form 26(21-05-2004).pdf

579-mum-2004-form 3(20-05-2004).pdf

579-mum-2004-form 8(07-06-2004).pdf

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